Pippa Middleton Scales the Matterhorn in Honor of Her Fiance's Brother, Who Died at 22 Climbing Mount Everest

The 32-year-old younger sister of the Duchess of Cambridge reached the summit with her own brother, 29-year-old James. The climb benefited the Michael Matthews Foundation, which was set up after Matthews' brother died while scaling Mount Everest in 1999. Michael was just 22 years old.

"It was humbling to have been able to climb one of the world's most beautiful mountains and raise money for a charity created in memory of an extraordinary young man who lost his life on another peak," Pippa told The Mail on Sunday. "Although I have raised money in the past for the Michael Matthews Foundation, it has now become even more important to me and my family."

"Although neither I nor my brother ever met Michael, we both share his spirit and passion for the mountains," she added. "We made this climb knowing he would have been there nudging us on, and we are honored to be supporting his memory."

Pippa shared that her fiance didn't climb the mountain alongside with her, as the memories of his younger brother's death are still devastating.

"It would have been good if my fiance James had been here to share the experience, something I know he would have loved to have done. Mountain climbing, though, has disturbing memories and understandably James kept his feet firmly on the ground, while giving us his complete support," she explained.

The Michael Matthews Foundation helps to provide an education to children in remote places.

Pippa is no stranger to daring climbs. She scaled Mont Blanc in 2008, again, alongside her brother.

But who will be a part of Pippa's wedding party, and will Kate be the Matron of Honor?! Watch the video below for all the details we know on what's shaping to be one of the most highly anticipated weddings in London!